1. Field of the Invention
This invention relates to instrumentations systems and, more particularly, to arbitrary waveform generator design.
2. Description of the Related Art
Signal generation is used in a wide variety of applications, including, for example, industrial testing and verification, product design, and control, among others. In one application of signal generation, a signal is generated according to waveform data, and provided as input or stimulus to a unit under test (UUT). Resulting output from the UUT may then be analyzed to characterize the UUT, e.g., for quality control, design feedback, etc. Generally, waveform generators are used to generate such signals.
Waveform generators may be used to produce one or more waveforms having defined characteristics. A waveform is a graphical representation of a signal, for example, an analog data signal or a digital data signal. The graphical representation may be a plot of amplitude (e.g., voltage) versus time. Therefore, a waveform representing an analog signal may comprise continuous and varying amplitude plots with respect to time (e.g., a sinusoidal wave), and a waveform representing a digital signal may comprise one or more pulses or discrete amplitude plots with respect to time (e.g., a binary pattern).
Waveform generators may be stand-alone systems or computer-based systems. In addition, waveform generators, also called signal sources, may be classified into two general types of waveform generators: arbitrary waveform generators and digital waveform generators. Arbitrary waveform generators are primarily used in analog and mixed-signal applications. Digital waveform generators, also called logic signal sources, include two classes of instruments: pattern generators and pulse generators. Logic signal sources are primarily used in digital system applications, for example, to provide stimulus signals, such as digital data patterns.
Waveform generators may generate waveforms by several methods. For example, waveform generators may create a waveform in response to a user input based on a plurality of waveform definitions. Additionally, waveform generators may create waveforms by receiving an existing signal and reproducing the signal. Furthermore, waveform generators may modify an existing signal. After creating, reproducing, and/or modifying a signal, waveform generators may output the one or more analog or digital signals.